public class HardDisk extends Object{
	int amount;
	HardDisk() {}
	HardDisk(int amount) {
		this.amount = amount;
	}
	public void setAmount(int a) {
		amount = a;
	}
	public int getAmount() {
		return amount;
	}
	public String toString() {
		return "HD已覆盖toString";
	}
	public boolean equals(Object obj) {
		return true;
	}
}

